


Nighttime Thoughts

by lbk_princen



Category: Ao no Exorcist | Blue Exorcist
Genre: Anxiety, Character Study, Emotional Baggage, Gen, Intrusive Thoughts, basically yukio grappling with whether or not to kill rin against fujimotos wishes
Language: English
Status: Completed
Published: 2020-09-11
Updated: 2020-09-11
Packaged: 2021-03-06 18:09:04
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,307
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/26403217
Author URL: https://archiveofourown.org/users/lbk_princen/pseuds/lbk_princen
Summary: Night after night, it was like this. Yukio, sleepless and haunted by what Fujimoto had revealed to him. Rin, sleeping soundly in ignorance of his own nature as well as his family’s, completely unaware of what he was and the threat he posed. Wouldn't the world be better off without the spawn of Satan?[Three nights, at three different points in their life. Not beta'd.]
Relationships: Okumura Rin & Okumura Yukio
Comments: 4
Kudos: 66





	Nighttime Thoughts

**Author's Note:**

> instead of working on any of my three wips i wrote this. take it

**[Age 5]**

Yukio woke to an unnatural tightness in his chest, a sort of pressure that made it hard to breathe. He gasped and sat up, tears already pricking his eyes as he gripped the bedsheets and glanced wildly around the room. In the dim glow of the nightlight, he could just make out the blurry shape of two red eyes leering at him from the shadows. 

The eyes were shrouded in darkness, but Yukio thought he could just barely make out the shape of a fuzzy body, the glisten of teeth. He drew the blanket up closer to his face, trembling. Rin’s bed was only a few feet away, and Yukio had never felt that distance between them so keenly.

“N-niisan,” the boy whimpered, breathing shallowly and unable to tear his gaze from the monster at the foot of his bed. “Niisan, wake up…”

Rin stirred and lifted his head. “Mm, what?” 

“There’s a demon,” Yukio whispered.

“Huh?” Rin looked around the room, but Yukio knew that his brother didn’t see the same things he did. “You’re being weird again, Yukio. Go to sleep.”

“Niisan, please,” Yukio choked. He was scared, paralyzed by the demon’s stare. He wanted it to go away. He wanted his chest to stop hurting. He wanted his dad. He wanted his brother to see it too, so that maybe he wouldn’t feel so alone.

“There’s nothing there,” Rin insisted grumpily as he threw off his covers. He slid out of bed and crawled into Yukio’s, pulling the latter’s attention away from the eyes momentarily. The elder twin made himself comfortable and tugged on his brother’s arm. “Come on, lie down. Nothing’s gonna hurt you, ‘kay?”

Yukio reluctantly followed the instruction and laid down beside his brother, tugging the blanket up like a shield over his head as Rin wrapped his arms around him. “I’m not making it up,” he mumbled. “I-it’s there, you just can’t see it… What if it wants to eat us?”

“Nothing’s gonna eat us,” Rin said, punctuating his assertion with a yawn. “Now just go to sleep.”

For a few seconds Yukio just listened to Rin’s breathing as it steadied and evened out. Fresh tears pricked at his eyes, because even as more and more seconds passed, the discomfort in his chest would not lessen. He knew that if he were to raise his head and lower the blanket, he would still see those inhuman red eyes glaring at him from the shadows. 

Why couldn’t Rin see them too? Why did he have to be so scared all the time? Why couldn’t he be more like his brother, boisterous and carefree?

Even there, wrapped in the arms and the warmth and the smell of his brother, Yukio couldn’t find the peace of mind to feel safe.

**[Age 12]**

Recently, Fujimoto had entrusted Yukio with a gun. He’d fired a gun for the first time when he was nine, and since then had been training diligently in how to use a firearm safely, correctly, and with accuracy, in that order. According to Fujimoto, Yukio had demonstrated that he was responsible enough that his father had no qualms with allowing him a personal firearm to keep with him, should he ever need it for self defense. Yukio, of course, had taken this with due solemness, and hadn’t removed his gun from its hiding place in his bedside table since placing it there.

It was nighttime, and Yukio couldn’t sleep. He was thinking about his gun, and the promise he’d made to his father, and the responsibility he had.

Five feet to his left, Rin was snoring.

The nightlight in their room had long been done away with, as Yukio no longer feared the low-level demons that sometimes made their way into the house. He was old enough now to understand the way the wards around the monastery worked - nothing class two or above could get in, but sometimes the more harmless types could slip past. He knew now that he had nothing to fear from them.

No, the only demon he ever encountered in his room that frightened him these days was his brother.

He hadn’t believed it, at first. Rin, a demon? His brave, stupid, amzing twin brother, a demon? How could it be possible? But the seriousness with which Fujimoto had confided in him was enough to convince him. The way that Rin got when he was angry (uncontrollable, like a wild animal - for years the only thing Yukio could do was cower and hope that he was never made the target of that fury) served as evidence.

In the darkness of their room, Yukio turned his head. Without his glasses on, lit only by the moon in the window, he could just barely see the fuzzy lump of shapes that indicated where his brother lay, still snoring away, oblivious.

Night after night, it was like this. Yukio, sleepless and haunted by what Fujimoto had revealed to him. Rin, sleeping soundly in ignorance of his own nature as well as his family’s, completely unaware of what he was and the threat he posed.

Yukio’s fingers bunched in the blanket as he thought again of the gun in his bedside table. It would be easy for him to get up, put his glasses on, and retrieve the gun without waking Rin. It would be easy to stand over his brother, unconscious, defenseless, gun in hand. It would be easy to point the gun, to pull the trigger, to rid the world of Satan’s spawn--

Yukio shook his head angrily to dispel the thoughts. Rin was still his brother. He’d promised Fujimoto he’d protect him. He knew Rin wasn’t evil - he saw it in the way his brother cared about other people and animals in a way that some perfectly ordinary humans couldn’t seem to manage.

Still, he remembered the last time Rin had thrown a tantrum. He’d smashed his fists into the kitchen table with a bloodcurdling scream, and the solid oak had splintered under the blow like it was plywood. Fujimoto said that Rin’s power would only grow as he got older - would he always be the compassionate older brother Yukio had looked up to? Or would there be a time when Yukio would look at his twin and see a monster instead?

Could he avoid that future by killing him now?

Yukio sat up suddenly, his breathing uneven. He didn’t  _ want _ to kill his brother but maybe - maybe he should anyway? Fujimoto said he could be dangerous, but  _ could _ doesn’t make any assurances one way or the other, and even though he was supposed to protect Rin, there was no way he would sit by and do nothing if Rin started hurting innocent people - but Rin wouldn’t do that - but a demon would, and Rin was a demon, so wouldn’t that mean--

“Yukio?” 

Yukio jumped, startled by his brother’s voice. Sweat prickled at his brow, and he squinted in Rin’s direction.

“What’s’a matter, can’t sleep?” Rin mumbled groggily as he sat up too, rubbing his eyes. “Your breathing’s all funny. Are you seeing stuff again?”

Yukio forced his breathing to slow and he pushed a smile onto his face even though he knew Rin likely couldn’t see it in the darkness. “No, no… I-I’m alright, niisan. Sorry if I woke you.”

“You can’t lie to me, little brother,” Rin said crossly. He tossed back the covers and padded over to Yukio’s bed. Yukio felt his chest tighten with fear, but all that happened was Rin joined him under his blanket and made himself comfortable against the pillow. “Come on, lie down already.”

Reluctantly, Yukio lowered himself back down. Rin didn’t hug him like he had when they were younger, but his weight and warmth in the bed still brought back memories of all the times Yukio had cried in the night, sad and scared and pathetic, and Rin had crawled into bed to comfort him. 

Despite the familiarity, it did not bring him a sense of comfort this time. “You can go back to your own bed, niisan. Really, I’m fine,” he insisted.

“Mmmmno,” Rin mumbled. “Too far now. S’nice ‘n warm here. M’gonna sleep.”

Despite the stress he felt, Yukio couldn’t help but roll his eyes. Stubborn Rin. He stared up at the dark ceiling as his brother breathed softly beside him. He tried to imagine sleeping in a silent room, Rin’s breathing and snoring completely absent. The thought put a pit in his stomach. 

The gun stayed where it was.

**[Age 15]**

There were still times when Yukio looked at Rin and wondered what would happen if he shot his brother right then and there.

He was less sure now than before Rin had awakened his flames that a single bullet would be enough to kill him. The only thing that frightened him more than the fact that he routinely considered murdering his twin, was the possibility that if he attempted it, he might fail.

Yukio was better trained, but Rin was stronger than him physically, and always had been. On the rare occasions that they had scuffled as kids, it was always Yukio who ended up in the dirt. Yukio felt he could probably take Rin down if he wasn’t expecting it, but that was without taking his flames into account. They still hadn’t seen the full measure of Rin’s power.

A snarl broke Yukio out of his thoughts. He’d been staring at the lesson plan he was supposed to have been working on while Rin slept in his bunk. Rin was now kicking in his sleep, and another inhuman noise ripped itself from his throat, forcing Yukio to his feet.

Instinctively, Yukio reached for the gun under his desk. He made sure it was loaded before slowly approaching Rin. There were no flames yet, but the demon’s face was screwed up in a familiar expression of fury that almost froze Yukio to the spot.

_ “Satan,” _ Rin growled, his whole body tensing and curling.

Yukio swallowed, his mouth suddenly dry. Was Satan trying to possess Rin? He couldn’t face Satan alone, he had to call for back-up, he had to--

The tension went out of Rin suddenly, and a sigh escaped his lips. Yukio inched a little closer and was surprised to see tears gathering on his brother’s eyelashes.

“Dad,” Rin murmured in the stillness.

Conflicting amounts of grief and relief rose, bitter, in Yukio’s throat. It was probably just a nightmare.

Admonishing himself for jumping to conclusions, Yukio switched the safety of his gun back on and returned it to its place. He glanced over at his brother, who was quiet now, breathing steadily but still with pinched eyebrows and wet cheeks. He couldn’t remember ever seeing Rin cry in his sleep before. It has always been him who had nightmares - afraid of demons, afraid of dying, afraid of Rin - but Rin had always done his best to make him feel better when it happened.

Maybe he ought to do the same for Rin.

Yukio crept over to Rin’s bed and carefully sat himself next to his twin’s sleeping form.

“Niisan,” he said quietly. When that got no response he gently shook Rin’s shoulder and tried again. “Niisan, wake up.”

Rin stirred. “Dad…?” He blinked, and his eyes focused on Yukio. “Yukio? Hmm?”

“It looked like you were having a nightmare,” Yukio explained patiently, ignoring the pang in his heart when Rin called for their dad once more.

“Oh.” Rin frowned and pulled away from Yukio’s hand on his shoulder. Under the blanket, his tail shifted. “I guess I was. Sorry.”

“You don’t have to apologize.” Yukio fiddled with his fingers in his lap. “Do you… want to talk about it?” he asked weakly. 

They still hadn’t talked about Fujimoto’s death. Not really. He knew Rin blamed himself, and the dark, bitter part of Yukio that he was always trying to smother blamed Rin a little bit too. But he had accepted his father’s death and mourned him privately. He didn’t see the need to air out all his conflicted and desperate emotions in the presence of someone else - especially not Rin.

Rin was uncharacteristically still for a moment. His expression was something sour and heavy. “I think, out of everything I’ve ever felt in my whole life, the thing I hated the most was feeling helpless,” he confided in a low voice.

Yukio interlaced his own fingers together and squeezed, a mimicry of what his heart was doing inside his chest. “I can relate to that,” he murmured.

The brothers sat there in the silence of their empty dorm for a few minutes. 

They had lived together their whole lives, and yet the secret of their heritage had made them almost like strangers. They were twins, but they couldn’t be more opposite - a demon and an exorcist. They sat now on one bed, sharing in each other’s silence and company, but it felt like there was a vast ocean between them. Yukio wondered if he would ever stop thinking about killing his brother. He wondered if Rin had ever thought about killing him, and realized right away that he hadn’t. Rin would never even consider it.

Which forced Yukio to think that perhaps if one of the Okumura twins  _ was _ evil, maybe it wasn’t Rin after all.

“You should go back to sleep if you can, Niisan,” Yukio said, his voice coming out stiffer than he intended. “You have class in the morning.”

“So do you,  _ sensei,” _ Rin shot back sarcastically.

The jab was rewarded with a sigh and an eyeroll, and Yukio stood up, leaving the warmth of his brother’s body behind in favor of returning to his desk. A familiar resentment chewed on Yukio’s tongue as he picked up his pen. “Goodnight, niisan.” 

“Goodnight, Yukio,” Rin mumbled back, oblivious.


End file.
